This research aims to establish a dialogue between the trauma theories of Sándor Ferenczi and Jean Laplanche, to enable to indicate their convergence points. Therefore, proceeded a bibliographical review to point out the specificity of each author’s thoughts. Ran through the life and work of Ferenczi to evaluate the author rescue and point out his major concepts about the trauma. Than, described Laplanche’s research, which emerges in a theorical renovation presented in the general seduction’s theory. In the end, we articulate the major concepts present in both authors to discuss the notion of trauma from them. We accentuated four conceptual axes to proceed to an theorical analysis: the psychic openning; the role for the other in the psychic constitution; the notion of body as parasited by desconnected representations and the notion of après-coup as caracateristic of human temporalization. As result, we caracterized two types of trauma as described by the authors: a fundamental trauma and the intromissive trauma. Also certificates that for these authors the psychic formation has an exogenous character implicated in the relationship with the original other, which pulsional messages affects the child, instituting the unconscious topic. So, we can think about the ethical aspects of the child’s care and the possibilities of psychoanalytical terapeutics.